Hacker attack on Twitter exposes confidential documents

A computer hacker has gained access to confidential documents of Twitter and some of its employees, and then forwarded the material to the technology news site TechCrunch.

The breach includes executive meeting notes, partner agreements and financial projections to the meal preferences, calendars and phone logs, according to TechCrunch.

Evan Williams, Twitter’s chief executive, confirmed the infiltration, emphasizing that it was corporate and personal information of employees that was compromised, not users’ Twitter accounts. He and his wife were among the victims.

“Obviously, this was highly distressing to myself, my wife, and other Twitter employees who were attacked,” Williams told TechCrunch. “It was a good lesson for us that we are being targeted because we work for Twitter. We have taken extra steps to increase our security, but we know we can never be entirely comfortable with what we share via email.”

The infiltration is attributed to someone going by the name of Hacker Croll, who made some of the information available to a French Web site yesterday along with TechCrunch. The same hacker had previously gained notoriety for getting access to the Twitter accounts of several Twitter employees and those of high-profile users Ashton Kutcher and Britney Spears.

In the latest incident, TechCruch said it was sent 310 documents showing the names of people who interviewed at Twitter for various senior level positions, floor plans and security pass codes to get into the Twitter offices.

Michael Arrington, TechCrunch’s founder, said that he wouldn’t publish some of the material because of its sensitivity, but he did post a pitch by a production company for a Twitter TV show. He promised to post financial projections, product plans and notes from executive strategy meetings.

The French Web site that also received some Twitter documents said included in the material is a projections showing that Twitter expects to have 25 millions users by the end of 2009, 100 million in 2010 and 350 millions in 2011. It’s not clear how recent the projections are.

Twitter currently has 21 million U.S. users, according to Nielsen Online and therefore may already have surpassed this year’s projection if overseas users are counted.